Trammel.



J. CHIUDO.

TRANIMEL.

APPLICATION FILED MAY'25,1918.

Patented Apr. 8, 1919.

@wi/Wm@ @WMV JOSEPH ameno-,or MINNEAPoLrs; .Mmnnsorn .TRAMMLL T'oaZZ whom t mayconoern." I i Be it' knownthat I, JosE'rrrCHroDo, a citif' zenA of the United'States,residingatMinne- Hennepin and' State' apol'is, in, the countygot y of 'Minnesotaifave invented new and useful Improvements-'win TrammelgOf, Whlfhvh'@ following is aspeciication be longitudinally extended.

. This invention relatesfto trammels espe cially adapted to be vused for drawingellipses and it consists inthe novel features hereinafter described and claimed.l

Anobject of thewinvention ist() provide an instrument'of the character"statedwhich is of simple structure yand Awhich may be` readily used for accurately establishing the point yupon a iield through ing line of an ellipse* passes. v

With this object in view the tranimelcomprises al frame having an arcuate side porintermedlate. legI m tion and a straight side portion which -describes the chord of together at one end and at a point exactlgT midway between the ends side of the frame and a handle is mounted upon the pivot which connects the legs together. Set screws are provided foryxing the legs with relation Yto the arcuate portion of the frame. The twoouter legs 'are' of the same lengthand cannot gated. The third intermediate legis longi` tudinally extensibleand maybe lengthene'd, Y l .Y one-half of the'A V,width or shortenedl as conditions will require.

ln the accompanyingdrawing:--V Figure 1 is a sideview of vthe trammel;

Fig. 2 is an edge elevation of'thet'rammel ;f Fig. 3 is a perspective illustration of the manner in which the instrument is operated.`

The trammel comprisesa framev which consists of astraight side l and anl arcuate chord of the arc of the sidey 2. Awpivot 3 is mounted on theside -1 at a point exactlyf midway between the ends of the side portion 2. A handle 4 is mounted -,onv the pivot 3.

outer legs 5 and 7 ofl the set of/legsfarel not susceptibleY of being adjusted longitudinally but lthe intermediate leg `may --The juppjer;

whichfthe boundg the arcor' the arcuateV portion. yThree legsr are pivotally connected ,tlonsf-wlll require.' Y

of the straight" to Vdelinezdean ellipse,

be extended or elon a sired Vdistancesl side portion 2.' The side. l. describes thev Legs 5,6 and 7 arepivotally con- Y nected'with` each. other by means ofthe pivot f `To accomplish` Y y Patented Api?. la;1.91.91. 'Applicatidred-'May25,miep-sentira;aaszs'; l d l y(this: theleg oo llnp'osetl"of"` two'sectionsll y ecation tubular, andfprovided with, a'setfs'erew 111'h which engagesthe" shank i I2 f* thefflower section `the. said shank is received@ y'in the tubular Nulziper'sectionfx `or' the?` leg 6152 Consequently cu-redfat; fthefadjlusted positions; more thejinftermediate legl may be; extended may beA positioned atV difeo i portion for`L the? l 'y A Y, A jit willfbe `l thelal'egsmay' beA,ad'jiistedl:along'thearcuatey portion 2` A'of the frame 'and by ftightening Ashereinbefcrestated the instrunientlis Y adapted." to beE-.fusedvgfor drawing o'rrdescfribT lng ellipses andthe outer legs 5 and '7 'may be spread aA sufficient distance apart; andi thev ay .be .positioned at 'a u desired point between the. outer' leg and maybe extended-or contractedas 'condi- In,` this'.` wayl the instrument isv operated This will. be better understood r when it` is stat'edthat prior to using `the trammeltwo A 'i 0 kas 's hownfin' Fig.` 3.v f yThe sizeY of the ellipse iis ldetermined by plac" axes must y be drawn,

ing ,limiting points on fthe l axeslof anyV del-l f mustgbe observedV that using .the device the and l0y are loosenedtoperlnit` the legs 5,

the vrail vThis rail 1`servesf as a guideto from the center, and caution i s the l. distanceslequal i to spread;and` move ifreelzy along which the legs .fare securelyheld intheir' i g proper positions `.while .the device is in use.

95T The leg VGis Yadjustable lengthwise, and rthe point onnsaid leg must. bef on the sameplane' fr as thepoints of the legs L5 and `7'. The. oper- .I

atorfspaces'fwith the two outer legs v5 and i 7 the distance equal to one-.halffof the major the rail l.y He ynextspaeeswvith the legsthe distancefequal to one-half .the minor axis.

leg 6 through the medium of thefthumb iofo Y axis. He then- -fastensyl the leg securely-4to l screw 9 and extends the leg lengthwise until` i thev point falls-on the same plane as the points-,ofthe legs .5 and'7.. 'f It will beunderstoodin this connection that the point; of the legtakesgfpo'sitions 0n all points on Y the minor axis ybetween the 'center andthe Q i Y extremity and the point of the leg 6 takes all 2 t p Y A1,300,122y

points on the major axis between the center KYnec'ted'` with a French curve;

andthe extremity. The point of the third leg 7 being'ina straight line to the pointsof the legs 5 and 6 establishes -the points through which the bounding line of the ellipse passes. These points are then con- It will be understoo-d from this that my novel device obviates the necessityof employing the inaccurate and slow straight edge.

Having described the invention what is 1. A trammel comprising a frame having an arcuate side portion and a straight side portion, the straight; side portion being a 1 chord of the arc of the arcuate side portion, a pivot carried upon the straight sidev portion at a point exactly midway between the ends of the arcuate portion, three legs movably mounted on the pivot and means for se curing the legs at adjusted positions upon the arcuate portion of the frame.

2. A traniniel comprising a frame having an arcuate side portion and a straight side portiom the straight side portion being a chord of the arc of the arcuate portion, a pivot mounted upon the straight side portion at a point exactly midway between the ends of the arcuate portion, three legs movably mounted on the pivot, means for securing the legs at adjusted positions upon the arcuate portion, the outer legs heilig nonextensible and the intermediate leg being longitudinally extensible.

In testimony whereof I aiX my signature.

JOSEPH CHIODO.

V Copies; ot this patent may be obtainedl for ve cents each, by addressing the Commissioner of Patents,

Washingtomnc. 

